Regular expression for photo name not working

Question

I am trying to use preg_match to have every photo whose filename is gallery\\album\\U[digits].jpg be titled "Untitled".

Here is the code:

foreach($photos as $photo){ 
  if (preg_match('.*U[0-9]*\.jpg',$photo)) {
    $title = "Untitled";
  }
  else {
    $title = basename($photo,".jpg");
  }
}

Any idea why this isn't matching? The title of any of these files ends up being "U2" or "U29".

Answer 1

Try,

if (preg_match('@U[0-9]+.jpg@',$photo)) {

DEMO.